Heidi Montag has been getting baby advice from Kristin Cavallari.

Kristin Cavallari

Kristin Cavallari

The 30-year-old reality television star - who is expecting her first child with her husband Spencer Pratt - has been in contact with her former 'The Hills' co-star and is asking "lots of baby questions".

She said: "Heidi has been asking me lots of baby questions. I'm so excited for her. I know she's been wanting a baby for a while."

And Kristin - who is a mother to sons Jaxon, two, and Camden, four, and daughter, Saylor, 17 months - revealed the first thing Heidi quizzed her on was baby names.

She added: "I was like, 'Heidi, this is your baby ... It's what you want to name your baby.' I sent her a whole list of things I loved as a as a mom [during] the first six months, because I remember being a first-time mom, I [didn't] really have anyone I could turn to."

And the 30-year-old star advised Heidi to stay positive as the first six months can be "really hard".

Asked what advice she'd give to new moms, she shared: "It can be overwhelming. It's the cliché things like sleep when the baby is sleeping, and just, like, knowing everything is a phase - knowing that everything will pass.

"The first six months are hard. They are really hard. Just know it will be over, you will be sleeping again. It gets easier. I thought it got easier as it went on, so everything is a phase."

And Heidi is not the first mom to have reached out to Kristin as she revealed Audrina Patridge also did so when she was pregnant with her daughter Kirra, now 10 months.

She told Entertainment Tonight: "Audrina reached out a lot when she was pregnant. It's really cool that they feel comfortable enough to come to me and that they look to me for that kind of advice."